. >> reporter: a lot riding on the race for both candidates tonight. vice-presidential joe biden and paul ryan. ryan will be trying to keep the momentum going for mitt romney. >> reporter: congressman paul ryan arrived at kentucky ahead of his first nationally televised debate. the number 2 man on the gop ticket told reporters earlier in florida, voters will see a clear choice when he faces off against vice president joe biden. >> joe biden has been on this stage before. he has been on these big stages. it's my first time. but what he can't run from is president obama's indefensible ortho. they are just offering more of the same. >> reporter: ryan will face an opponent who occasionally causes controversy with freewheeling statements but republicans also know vice president biden is a seasoned debater. >> nothing like standing up before 20, 30, 40, 50, 60, 70 million people. >> reporter: usually vice- presidential debates don't greatly impact elections but after the president's lackluster performance at the first debate with mitt romney, many believe de